Challenge Prompt: Write about a character sacrificing him/herself for another.
Setting: Godric's Hollow, October 30th, 1981
'So that's why they're unbeatable.'
Lily sat back on her feet, hard. She was on the floor of the nursery, her ever-present worry not permitting her to leave her son's side any longer than necessary. Scattered before her were reams of paper, her personal notes and research combined with every scrap of information she could collect on what she called "unbeatable magic".
Most magic, she had found, focused power to very specific effect. The right wand movements and incantation would shape the magic to be more suitable to the desired end, but those effects could be undone.
A protego charm was magic shaped into a defensive barrier, fueled by the desire to protect and shield. Yet given enough power and hate, a cutting curse could still rip through it, leaving a man walking on a wooden leg for the rest of his life.
The obliviate claimed to erase memory, but the mind was not so easily erased. There were traces that allowed even the strongest obliviate to be undone, if magic or willpower of sufficient strength were set against it. The trauma of, for instance, being almost murdered by a werewolf and being betrayed by man he thought he could trust, combined with the most disciplined mind she had ever seen, allowed a man she once called friend to overpower a very thorough obliviation and realize how completely he had been wronged. For all her sorrow and hatred, she wasn't sure she blamed him for his choices after that.
Why, then, were some spells different? Enough magic could destroy even the most powerful wards, but a fidelius was unbeatable. It had a trick, certainly, but no magic could overcome it, no power could simply undo it. If you weren't given the secret, you could not gain entry.
And no magic could block the unforgivable curses. Nobody she spoke to had ever been able to explain why, usually claiming that nobody knew.
Another lie, as it turned out. The spells weren't any different, they just invoked an extra principle, without which no counter could ever work. Each spell had its own unique twist, well guarded secrets that if known would have rendered them all but useless. She supposed she could understand the secrecy, given that such secrecy was all that preserved their effectiveness, but…
She had started with the fidelius. She was trusting her family's life to it, after all, so why should she assume it was truly unbreakable? She learned that in the depths of the Ministry, in one of the vaults of the Unspeakables there was a tome which listed all known castings of the fidelius.
"Kill me then", snarled Rookwood, "If your kind is capable of it."
Lily smiled as she held Rookwood at wand point, and he was surprised to find himself shivering before her gaze. "You don't want to know what I'm capable of, Augustus. Albus believes in mercy, I believe in protecting my family."
Rookwood was surprised to find a glimmer of respect growing inside of him. Growling he shrugged it aside. "Why haven't you then?"
"Because you're going to help me." Lily's gaze never left his.
"You're mad! What makes you think I would ever lower myself to helping a mudblood?"
"Because you're not a zealot. You work in the Department of Mysteries, feeding misinformation to our side and giving your master valuable intelligence." Lily's smile faded. "You've done a lot of damage in the name of your master, and it would do my side a lot of good to put you down right now." She stepped back and looked him over. "Imagine how upset your master would be if he lost such a valuable resource. Wouldn't it be better to come to an arrangement that lets you keep your position?"
Rookwood narrowed his eyes. "What sort of arrangement? I'm not going to betray the Dark Lord."
"Of course not. There's a book, only one copy left anywhere. 'Secrets of Secrets.' You know it?" He shook his head and she smirked. "Excellent. Here's how this works. We're going to swear an unbreakable vow, you and I. I have a very long and thorough version for you to read over, but basically you'll be getting me the book, without learning what it's about or betraying me in any way, and in exchange I let you live and agree to keep your position secret."
"What's in this book that's so important to you?" Rookwood tipped his head.
"Not part of the deal. Either you swear the vow, here and now, or you die. Which will it be, death eater?"
Three days later she had the book. Two days after that, she found the only account of a fidelius being defeated, and along with it, the hidden key to its strength.
Faith.
Trust, more specifically, the faith those who hide have in their secret-keeper to guard their location. Even if that trust wavered after the charm was cast, it was imbued into the very essence of the shield. It could only be overpowered by an equally strong belief that the shield could be broken.
Since everyone knew the fidelius was unbeatable, that wasn't a problem, or so reasoned the few scholars who knew the truth.
Lily closed her eyes as she remembered the passage that had shown her the truth.
Long had Terik suspected his wife of infidelity. Ever he sought to find his wife and his best friend together, not believing them when they proclaimed their innocence. When one day he could not find their home, he grew enraged. This was proof, he knew, that they would go to any length to hide themselves and their tryst from his eyes.
Though his friend's home was hidden, he knew where it was nevertheless. Knowing he had always been stronger, he did not hesitate to use the most powerful ward hammer he knew. His satisfaction that his spell worked was matched only by his fury to find that he was wrong. His wife had been unfaithful, but with his best friend's sister; his friend had been a willing accomplice, enabling their meetings. In the depths of his rage, he conjured the cursed fiendfyre to consume them all.
Much later, when asked how he broke a fidelius charm, he was surprised to hear of it. He hadn't known the charm existed, much less that it was unbeatable, and wasn't impressed by it.
Absolute confidence that the shield could be broken combined with general knowledge of the right location. Those were all it took to break a fidelius.
Their home had been a matter of public record, and no doubt Voldemort would be able to work out approximately where they were. As for absolute confidence, well, the monster grew more insane day by day and was convinced he was the strongest wizard to ever exist. There might be a sliver of doubt in his mind still, but Lily wasn't willing to gamble her son's life on that.
She couldn't tell James or Albus how she had come to these conclusions without revealing the book, something the Vow prohibited. Without that explanation, she had been unable to convince them of the charm's vulnerability.
So she threw herself back into her research, seeking a way to counter the unforgivables. If she could do that, she could turn the tide of the war and ensure her family's safety. She scoured every book, every secret account she could find; from the Ministry, from Hogwarts' forbidden library, from contacts overseas, even muggle books of legends and myths; no potential lead was too obscure, too unlikely to be worth following to its end.
The secrets of the Imperius were the first to fall, scribbled away on the back of an old epic poem, about the ancient sirens of Greece. The Imperius was unblockable by your magic because it reached out to your magic, turned it against you in service of the caster. There was no bolt, no projectile, it simply manifested inside of your magic and acted. Strangely, muggles were not immune, a fact the author had used to argue that even muggles possessed some magic, no matter how slight. She had desperately wanted to pursue that line of inquiry, but the more immediate concerns of the war drew her back.
To block the Imperius, you had prevent your magic from being reached at all. Not knowing if it was possible to completely cut a wizard's magic off without killing him, she had set the topic aside and moved on.
She had ignored the Cruciatus curse. As horrible as it was, there was rarely an opportunity on the battlefield for it to do irrevocable damage, and it took enough energy to cast that it was risk for the caster as well as the target.
So at last, she came to the killing curse. This had been the most elusive, requiring another tome from the Department of Mysteries. This time, she had done the job herself.
She ignored the spellfire flying around her as she darted down a corridor.
"Lily!" She heard James cry out behind her.
"Prongs, she can handle herself, stay sharp!" Sirius retorted, pulling James out of the way of an incoming curse.
'Sorry James, I'll make it up to you later' she thought to herself as she pushed deeper in. The Death Eaters had launched a full out raid on the Department of Mysteries, though nobody in the Order knew why. She ran toward a chamber she had seen earlier, one filled with books, only to pull up short as she saw Rookwood digging furiously through the largest pile. He looked up as she stopped in the door.
"You! What are you doing here?" He pulled his wand.
"Me? I'm just helping the death eaters attacking, of course, just like you're here protecting the books, right?" She smirked. "We could fight and draw attention, or just grab what we want and be gone before anyone notices."
Rookwood growled, but returned his attention to the pile of books in front of him. Looking at the pile, she saw the book she wanted tumbling down the pile toward her. She leapt forward and grabbed it, noting that Rookwood glanced up at it as she did so. A look of surprise crossed his face.
"'Divining the Dementors'? That's a dark book for a member of your order, isn't it?"
Lily shrugged. "Recreational reading. There are so few books worth reading these days, don't you agree?" She backed slowly out of the room, and once she was clear, twisted and apparated out of the Ministry.
James had never thought to question her story about following a death eater, or that she'd had to apparate out to avoid a killing curse.
The book, long thought to be a study of the dementors themselves, was in fact a study of their effects on humans and the various ways you might replicate the effect. A book from Hogwarts' library had implied the creator of the killing curse had gotten the idea from this lost tome, and if there was anywhere she might find the missing key to its nature, it was within those pages.
She looked back at the floor in front of her, the last two pages showing the truth of the curse.
"For those who wish to invoke the dementor's power to kill without limit or impairment, know that they strike not the life's blood, but the soul and its potential. When one dies to the dementors, they consume all the potential of that person's life, every moment of joy and happiness they might ever have experienced. Thus, are they robbed of life, though their body may yet live on. Even if the essence of their soul could be restored, there would be nothing to return for, all of their life's potential consumed.
This, then, is the power you will wield, a power that will render you unbeatable in battle. A ritual call, woven into the essence of the spell, shortened to a form useful for combat."
She had ended the translation charm on the ritual itself, letting it revert to unintelligible hieroglyphics. Reading it once was enough, she had no desire to read it again. A ritual chant, the stanzas' first characters spelling out the words that had been feared for so long in the wizarding world.
Avada Kedavra.
Unbeatable, because the power it brought to bear was the power to destroy not just life as it was, but all the potential the soul yet possessed. What power could possibly compare?
She grew still, as a horrible thought came to her. How far would she go to protect her son?
A laugh drew her attention to the crib. Standing, she looked down on her son's face, blissfully innocent of everything that was happening around him. She reached down to stroke his face, and he grabbed her hand and laughed.
"Oh, Harry…"
"...Ma...ma…" Hearing that, she knew that there was nothing she would not do for her son.
She sat back down and began writing.
"Lily, take Harry and go! It's him! I'll hold him off!" James' cry sounded up the stairs.
'How strange that it comes now.' She hadn't slept, hadn't told anyone what she was doing. Even James had been kept in the dark, as she drew symbol after symbol across her body, taking great care to hide them all under her clothes where they would not be seen. She had almost finished, had just one last thing to do, when she heard James' panicked call.
Standing, she leaned over her son. Painting the last symbol, a lightning bolt on his forehead, she gave thanks to anyone that might be listening that his hair was long enough even at this young age to conceal it.
As the door burst open, she spun. Voldemort stood before her, as terrifying as he had ever been.
"Stand aside, woman."
"No, you'll not kill my son." She stood, keeping herself between her son and the monster before her..
Voldemort gestured, and Lily found herself flung to the side. "The Dark Lord keeps his promises. You are not to die this day, only the boy." Stepping forward, he pointed his wand down at the infant in the crib. "Avada Kedavra!"
The green light lanced toward Harry Potter, only to rebound off his forehead, striking Voldemort as it came back. Voldemort scarcely had time to look surprised, and in a flash of green light, his body disappeared.
Lily smiled, as she looked down at herself. Her body was already starting to fade. Standing, she looked at the picture of their family that always stood beside Harry's crib. Already, she had disappeared from it.
The killing curse took a life, and to counter it, a life had to be given.
The killing curse destroyed every bit of potential that life had once held, every possible moment of joy and happiness it would ever experience. To counter that, one had to give an equal amount of potential.
Lily smiled as she looked down at her son for the last time, her son for whom she had given not only her life, but her entire existence, every moment she had lived since she had been Harry's age and all the moments she would never know.
"Goodbye, Harry." She whispered, and the last thing she saw before fading away was the green of her son's eyes.
A wind blew through the room, and Harry reached out toward where she had stood just moments prior.
"...Ma...ma…"